"We need to pass the bill, to see what's in it" – Nancy Pelosi

Twentieth Amendment

SECTION 1.

The terms of the President and Vice President shall end at noon on the 20th day of January, and the terms of Senators and Representatives at noon on the 3d day of January, of the years in which such terms would have ended if this article had not been ratified; and the terms of their successors shall then begin.

“The terms of the President and Vice President shall end at noon on the 20th day of January, and the terms of Senators and Representatives at noon on the 3d day of January” – On January 20th at noon (EST, I assume), the current term of the President and Vice-President end. Also, on January 3rd at noon (EST, I assume), the current term for all Senators and Representatives come to a close.

“of the years in which such terms would have ended if this article had not been ratified; and the terms of their successors shall then begin.” – If anyone was at their term limit, their successors’ first term would begin. This is why it’s important that all elections are done ethically and officially certified.

SECTION 2.

The Congress shall assemble at least once in every year, and such meeting shall begin at noon on the 3d day of January, unless they shall by law appoint a different day.

Since a new term will have started for all members of Congress, they meet at noon (EST, I assume) for the first time to get everyone acquainted and started.

This section also gives Congress the power to change the date of this meeting by passing a law.

SECTION 3.

If, at the time fixed for the beginning of the term of the President, the President elect shall have died, the Vice President elect shall become President. If a President shall not have been chosen before the time fixed for the beginning of his term, or if the President elect shall have failed to qualify, then the Vice President elect shall act as President until a President shall have qualified; and the Congress may by law provide for the case wherein neither a President elect nor a Vice President elect shall have qualified, declaring who shall then act as President, or the manner in which one who is to act shall be selected, and such person shall act accordingly until a President or Vice President shall have qualified.

“If, at the time fixed for the beginning of the term of the President, the President elect shall have died, the Vice President elect shall become President.” – If at the beginning of a president’s new term, that president had or does die, the Vice-President becomes President.

“If a President shall not have been chosen before the time fixed for the beginning of his term, or if the President elect shall have failed to qualify, then the Vice President elect shall act as President until a President shall have qualified;” – If no president is chosen before the beginning of their term, the current Vice-President becomes President, until someone is found/elected.

“and the Congress may by law provide for the case wherein neither a President elect nor a Vice President elect shall have qualified, declaring who shall then act as President, or the manner in which one who is to act shall be selected, and such person shall act accordingly until a President or Vice President shall have qualified.” – If neither a president or vice-president is deemed qualified or chosen by the start of the term, Congress may act to choose someone to fit both slots, until two people deemed qualified, are chosen.

SECTION 4.

The Congress may by law provide for the case of the death of any of the persons from whom the House of Representatives may choose a President whenever the right of choice shall have devolved upon them, and for the case of the death of any of the persons from whom the Senate may choose a Vice President whenever the right of choice shall have devolved upon them.

Congress may authorize or pass a law delegating the House and Senate to choose a President and Vice-President, upon death of either.

SECTION 5.

Sections 1 and 2 shall take effect on the 15th day of October following the ratification of this article.

Authorizes Sections 1 and 2 to take effect on October 15th, post-ratification.

SECTION 6.

This article shall be inoperative unless it shall have been ratified as an amendment to the Constitution by the legislatures of three-fourths of the several states within seven years from the date of its submission.